A background in dynamical systems is essential to any mathematical modeling in biology. In fact, most game theory problems can be written as a form of dynamical system problem where you're looking for some steady state. I'd suggest picking up Nonlinear Dynamics and Chaos by Strogatz.
Dear Mr. Chris, Thank you for the reply. However I have only a basic knowledge in mathematics. So can I understand the mathematical treatment in the book, or should I first learn some other topics?
Dynamical systems really only needs knowledge of Calculus (Differential Equations) and Linear Algebra. Strogatz is an easy read that many places use to introduce the concepts to "non-math" people.